What is the desired angular change to the flight path achieved by the pitch maneuver performed after clearing the launch tower?

What are typical pitch angles for current LVs such as Atlas V, Ariane 5 etc.?

No guideline. It depends on other requirements. Usually (1) controllability, (2) structural limits, (3) performance (drag) in that order of importance.

Very small compared to airplanes (quantification could involve eye tar so don't ask). While q is still high, much of an alpha or beta will cause tumble or tearing off the fairing. Which is why the constraint is often listed in terms of q*alpha or q*beta.

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If I like something on NSF, it's probably because I know it to be accurate. Every once in a while, it's just something I agree with. Facts generally receive the former.

...because access to emergency landing sites, aerodynamic surfaces and the lack of fairing separation (altitude) make the Shuttle a special case muddying the water when trying to understand the basics as in Basic Rocket Science Q&A.

No guideline. It depends on other requirements. Usually (1) controllability, (2) structural limits, (3) performance (drag) in that order of importance.

Very small compared to airplanes (quantification could involve eye tar so don't ask). While q is still high, much of an alpha or beta will cause tumble or tearing off the fairing. Which is why the constraint is often listed in terms of q*alpha or q*beta.

My guess for its purpose is to gain just enough vertical speed during the 1st stage burn so that the LV does not drop back below fairing separation altitude. It is an issue when the upper stage thrust/weight ratio is below 1. Since the angle of attack during atmospheric flight is rather limited I am speculating that the initial pitch maneuver is supposed to put the vehicle on a trajectory that limits vertical v to exactly meet this requirement, but again, I'm not sure this is the case.

1. mentions a 10 s pitch rotation. ....... My question is not so much about structural limits but about how much the LV is put off the initial 90 deg climb angle? Maybe it rotates to 70 or 80 deg during those 10 s?

2. My guess for its purpose is to gain just enough vertical speed during the 1st stage burn so that the LV does not drop back below fairing separation altitude. It is an issue when the upper stage thrust/weight ratio is below 1. Since the angle of attack during atmospheric flight is rather limited I am speculating that the initial pitch maneuver is supposed to put the vehicle on a trajectory that limits vertical v to exactly meet this requirement, but again, I'm not sure this is the case.

1. There are other "pitch rotations" in the flight. This is not the only one. Also a "pitch rotation" is a rate and not a final position.

2. Since there are other "pitch rotations", and the vehicle attitude is not fixed, therefore the rest of your post is not applicable.

The initial pitch rates and attitudes are about structural limitations and aerodynamic loads. Pitch rates and attitudes to deal with gravity losses and second stage start conditions occur later.

1. There are other "pitch rotations" in the flight. This is not the only one. Also a "pitch rotation" is a rate and not a final position.

Let me phrase the question differently then:

Do LVs actively aim for non zero angle of attack at any time during supersonic flight?

If not, then it needs to be tipped off initially, i.e., after clearing the tower and by some angle that I'm interested in. Thereafter, it does a gravity turn. Well, I hope gravity turn is the proper term for aligning thrust and velocity vectors to achieve zero AOA.

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2. Since there are other "pitch rotations"...

... would mean my assumption is wrong which is LVs strictly stick to a gravity turn during atmospheric flight and after the first few seconds of ascent - UNLESS those other pitch rotations are performed for the very reason of keeping the AOA continuously close to zero?

...because access to emergency landing sites, aerodynamic surfaces and the lack of fairing separation (altitude) make the Shuttle a special case muddying the water when trying to understand the basics as in Basic Rocket Science Q&A.

You are correct the shuttle is a little different, but it still must not fall apart during first stage and fly an optimum pitch profile in second stage. Someone in the shuttle world can get you a copy of the pitch profile cue card used by the crew. Try googling "SODB". You might try the Apollo forum to get a copy of the Apollo cue card. The is a Saturn V users manual on the web that I think has a copy.

Have you tried the Atlas and Delta User's guides? I would help find links, but I am on my Treo.

The launch vehicles often don't shoot for zero angle of attack. But must always keep angle of attack in limits.

1. Do LVs actively aim for non zero angle of attack at any time during supersonic flight?

2. If not, then it needs to be tipped off initially, i.e., after clearing the tower and by some angle that I'm interested in. Thereafter, it does a gravity turn.

3. Well, I hope gravity turn is the proper term for aligning thrust and velocity vectors to achieve zero AOA.

4. ... would mean my assumption is wrong which is LVs strictly stick to a gravity turn during atmospheric flight and after the first few seconds of ascent - UNLESS those other pitch rotations are performed for the very reason of keeping the AOA continuously close to zero?

1. LV's don't sense AOA or even airspeed. Everything is based on simulations and balloon data

FYI, found some reference material in the meantime. Depicted below are the diagrams for pitch and AOA taken from the Saturn V Flight Manual. It shows that AOA peaks at 4 deg shortly after clearing the tower. Then it stays below 1 deg during atmospheric flight. So, the Saturn V first stage is so kind to behave following my intuition: That is, actively pitch over to some precomputed attitude early on and then just duck the oncoming airflow.

The same with Atlas V; the payload user manual says: At an altitude of 244 m (800 ft) and time from liftoff greater than 10 seconds, the vehicle begins its initial pitch-over phase. At approximately 2,438 m (8,000 ft), the vehicle enters into a nominal zero-pitch and zero-yaw angle-of-attack phase to minimize aerodynamic loads.

It also mentions an optional alpha-bias angle-of-attack steering mode between 80-120 Kft to account for wind.

FYI, found some reference material in the meantime. Depicted below are the diagrams for pitch and AOA taken from the Saturn V Flight Manual. It shows that AOA peaks at 4 deg shortly after clearing the tower. Then it stays below 1 deg during atmospheric flight. So, the Saturn V first stage is so kind to behave following my intuition: That is, actively pitch over to some precomputed attitude early on and then just duck the oncoming airflow.

The same with Atlas V; the payload user manual says: At an altitude of 244 m (800 ft) and time from liftoff greater than 10 seconds, the vehicle begins its initial pitch-over phase. At approximately 2,438 m (8,000 ft), the vehicle enters into a nominal zero-pitch and zero-yaw angle-of-attack phase to minimize aerodynamic loads.

No, you are still getting it wrong. Read the top chart, attitude goes from 0 to 60 degree

The pitch rate doesn't go to zero. there still is one (the actual attitude is changing), it is just at a slow rate as to not generate an angle of attack. This is not "ducking". The incoming flow is the velocity vector.

A vehicle could fly straight up and hence would not generate an angle of attach. But because a more efficient trajectory requires the vehicle to go horizontally eventually, the vehicle has to pitch over to turn the velocity vector. The rate at which it does is a function of structural limitations and the propulsion system.

Sure, it was never claimed that it's zero. My initial point in reply 178 was about initiating the gravity turn and how much it typically takes to do so. It was not well phrased though because the term pitch over phase was missing from my vocabulary. AOA vs. pitch rate is clarified. Thanks for your patience.

Anything you're going to find publicly is also going to be very generic. In the real world, every single one of these is going to be mission unique.

It's like the cone vs the black line in hurricane forecasting. You seem to be trying to calculate a black line that's the same for every mission. In reality, there are just bounds on what the rocket can do (the cone). How it flies on launch day, the black line withing the cone, is subject to a long list of variables, requirements and optimizations of same. Where one rocket might be flying a steady zero or non-zero alpha, another one would be pitching. It's truly unique to each mission.

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If I like something on NSF, it's probably because I know it to be accurate. Every once in a while, it's just something I agree with. Facts generally receive the former.

Anything you're going to find publicly is also going to be very generic. In the real world, every single one of these is going to be mission unique.

It's like the cone vs the black line in hurricane forecasting. You seem to be trying to calculate a black line that's the same for every mission. In reality, there are just bounds on what the rocket can do (the cone). How it flies on launch day, the black line withing the cone, is subject to a long list of variables, requirements and optimizations of same. Where one rocket might be flying a steady zero or non-zero alpha, another one would be pitching. It's truly unique to each mission.

AntaresThat is perhaps the very best example I have ever seen for any rocket's actual performance vs. its predicted performance.

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Chuck - DIRECT co-founderI started my career on the Saturn-V F-1A engine